@article {1817,
title = {NAO and PNA influences on winter temperature and precipitation over the eastern United States in CMIP5 GCMs},
journal = {Climate Dynamics},
year = {2015},
month = {07/2015},
abstract = {The historical and future relationships between two major patterns of large-scale climate variability, the North Atlantic Oscillation (NAO) and the Pacific/North America pattern (PNA), and the regional winter temperature and precipitation over the eastern United States were systemically evaluated by using 17 general circulation models (GCMs) from the Coupled Model Intercomparison Project phase 5. Empirical orthogonal function analysis was used to define the NAO and PNA. The observed spatial patterns of NAO and PNA can be reproduced by all the GCMs with slight differences in locations of the centers of action and their average magnitudes. For the correlations with regional winter temperature and precipitation over the eastern US, GCMs perform best in capturing the relationships between the NAO and winter temperature, and between the PNA and winter temperature and precipitation. The differences between the observed and simulated relationships are mainly due to displacements of the simulated NAO and PNA centers of action and differences in their magnitudes. In simulations of the future, both NAO and PNA magnitudes increase, with uncertainties related to the model response and emission scenarios. When assessing the influences of future NAO/PNA changes on regional winter temperature, it is found that the main factors are related to changes in the magnitude of the NAO Azores center and total NAO magnitude, and the longitude of the PNA center over northwestern North America, total PNA magnitude, and the magnitude of the PNA center over the southeastern US.},
keywords = {CMIP5, NAO, PNA, Regional climate, teleconnection},
issn = {1432-0894},
doi = {10.1007/s00382-015-2643-9},
author = {Ning, Liang and Bradley, Raymond S.}
}
@article {1240,
title = {Natural archives, changing climates},
journal = {Contributions to Science},
volume = {7},
year = {2011},
pages = {21-25},
abstract = {Climatic changes have occurred throughout human history, but instrumental measurements do not provide us with a very long perspective on climate variations. In many regions, instrumental records only extend back a century or two. To understand the longer-term variability of the climate system, we rely on natural archives- sediments, ice caps, peat bogs, cave deposits, banded corals and tree rings-in which a record of past changes in climate has been preserved. They are a treasure trove of the climatic and environmental history of the planet and provide information about factors that may have caused the climate to change, such as major explosive volcanic eruptions, changes in solar irradiance and human effects on the atmosphere. Paleoclimate archives show that the world has experienced very different conditions from today, even in the recent past, and they provide a framework for us to assessthe magnitude of future changes that we are likely to experience as greenhouse gases continue to accumulate in the atmosphere. Societies in the past have been disrupted by abrupt and unexpected climate changes, and the paleoclimatic evidence demonstrates our vulnerability to rapid shifts in climatic patterns. Unfortunately, many of the natural archives that provide this unique perspective on past climate are now under threat by human activities, and the very climatic changes that we seek to understand.},
keywords = {climate, paleoclimatology},
url = {http://revistes.iec.cat/index.php/CtS/article/view/54461},
author = {Bradley, Raymond S.}
}